MESOSCALE PRECIPITATION DISCUSSION 0231
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1205 AM EDT WED MAY 30 2018

AREAS AFFECTED...CETNRAL AND EAST CENTRAL AL

CONCERNING...HEAVY RAINFALL...FLASH FLOODING LIKELY

VALID 300405Z - 300815Z

SUMMARY...CONVECTIVE DEVELOPMENT WITH SOME POTENTIAL TRAINING
TRAVERSING SATURATED SOILS IN CENTRAL AL LIKELY TO LEAD TO FLASH
FLOODING IN THE NEAR TERM

DISCUSSION...GOES-16 10UM IR DEPICTS TWO  RAPIDLY COOLING
CONVECTION CLUSTERS ACROSS CENTRAL AL WITH OVERSHOOTING TOPS TO
-65C. REGIONAL RADAR CONFIRMS TWO SW TO NE LINE SEGMENTS AT THE
NOSE OF CONFLUENT SFC TO 850 MB FLOW AS WELL AS THE NOSE OF
INSTABILITY AXIS WITH SBCAPES TO 2000 J/KG. THOUGH WINDS ARE WEAK
THE CONVERGENCE IS SUFFICIENT FOR FURTHER DEVELOPMENT WITH MEAN
CELL MOTIONS NEAR OR JUST EAST OF THE ORIENTATION OF THE BAND. 
AVAILABLE DEEP MOISTURE WITHIN THE UPDRAFTS WILL SUPPORT RATES OF
1.5-2"/HR AND COULD ADD AN ADDITIONAL 2-3" OVER THE NEXT 2 HOURS
BEFORE MOVING INTO MORE STABLE ENVIRONMENT FURTHER NE UP THE
CONVERGENCE BAND.  THIS RAINFALL IS ALSO LIKELY TO FALL ACROSS
AREAS AFFECTED BY 3-4" OF RAIN FROM ALBERTO LAST EVENING MAKING
FLASH FLOODING LIKELY GIVEN FFG VALUES HAVE FALLEN IN PARTS TO
1.5-2.0"/3HRS.  SLOW ENE TRANSLATION OF THE LINE SEGMENTS WITH
SOME POTENTIAL OF MERGING AS WELL AS SOME WEAKER SHALLOWER
CONVECTION (DUE TO LESS AVAILABLE INSTABILITY) DOWNSTREAM IN EAST
CENTRAL AL MAY HAVE THE POTENTIAL FOR HIGHLY LOCALIZED FLASH
FLOODING THREAT DUE TO HIGHER FFG, LESS SATURATED GROUNDS, AND
LOWER AVAILABLE INSTABILITY TO MAINTAIN STRONGER UPDRAFT FOR
RAINFALL PRODUCTION. 

GALLINA

ATTN...WFO...BMX...MOB...

ATTN...RFC...SERFC...

LAT...LON   33928591 33548537 32998533 32478559 31878611
            31718747 31978772 32248779 32688758 32838736
            33328661